Fiber optic cables allowing fiber translation to reduce bend attenuation

ABSTRACT

A cable includes a channel with an aspect ratio that houses optical fibers therein. The cable includes first and second stranded conductors on opposing sides of the channel. The channel is arranged with respect to the stranded conductors so that the fibers assume low strain positions in the channel when the cable is bent.

RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.13/489,867, filed on Jun. 6, 2012, which claims the benefit of priorityand U.S. Application Ser. Nos. 61/588,950 filed on Jan. 20, 2012, and61/495,732 filed on Jun. 10, 2011, the contents of which are relied uponand incorporated herein by reference in their entireties.

BACKGROUND

1. Technical Field

The present disclosure generally relates to fiber optic cables havingcavities or channels that allow optical fibers to translate duringbending to reduce bend-induced attenuation.

2. Technical Background

As the use of fiber optics migrates into numerous consumer electronicsapplications, such as connecting computer peripherals, there will be aconsumer-driven expectation for cables having improved performance and abroad range of use. For example, it is likely that consumer demand willbe for a fiber optic cable having a small footprint (e.g. a cable outerdiameter less than 3.0 millimeters (mm)) while at the same beingflexible enough to “bend back” upon itself.

However, optical performance and optical fiber integrity are adverselyaffected by cable “bend back.” FIG. 1 shows a typical fiber optic cablein a bent back configuration. The fiber optic cable 2 is generallycircular and has an outer bend periphery 16 and a cable diameter orthickness 6. Internal to the cable is an optical fiber 10, which carriesdata. When the fiber optic cable 2 is bent back as shown, a bend radius8 is at a minimum and is approximately equal to the cable diameter 6.The location of the optical fiber 10 within the cable 2 will affect abend radius 12 of the optical fiber 10. If the optical fiber 10 is closeto the outer bend periphery 16, the fiber will have a larger bend radiusand experience lower attenuation. If the optical fiber 10 is closer tothe inner portion of the cable, the bend radius of the fiber will besmaller and cause greater delta attenuation due bending. If the bendradius 12 is small enough, the optical fiber may crack at an outersurface 18 of the optical fiber 10 and cause cracking or fracture of theoptical fiber 10.

SUMMARY

According to one aspect, a fiber optic cable comprises a polymer jackethaving a channel therein, at least one optical fiber in the channel, afirst electrical conductor on a first side of the channel, and a secondelectrical conductor located on an opposite side of the channel to thefirst conductor, wherein the channel has an aspect ratio calculated bydividing a height of the channel by a width of the channel of at least1.5.

BRIEF DESCRIPTION OF THE DRAWINGS

The components of the following figures are illustrated to emphasize thegeneral principles of the present disclosure and are not necessarilydrawn to scale. Reference characters designating correspondingcomponents are repeated as necessary throughout the figures for the sakeof consistency and clarity.

FIG. 1 is a cross-sectional view of a typical prior art fiber opticcable in a bent back configuration, wherein the cross-section isparallel to a length of the cable.

FIG. 2 is a cross-sectional view of a fiber optic cable according to afirst embodiment of this disclosure, wherein the cross-section is atransverse cross-section perpendicular to a length of the cable.

FIG. 3 is photograph of a cable cross-section according to an embodimentof this disclosure.

FIG. 4 is photograph of a cable cross-section according to an embodimentof this disclosure.

FIG. 5 is a cross-sectional view of a fiber optic cable according to asecond embodiment of this disclosure, wherein the cross-section is atransverse cross-section perpendicular to a length of the cable.

FIG. 6 is an exploded perspective view of the cable of FIG. 5.

FIG. 7 is photograph of a cable cross-section according to an embodimentof this disclosure.

FIG. 8 is a transverse cross-sectional view of a fiber optic cableaccording to a third embodiment of this disclosure.

FIG. 9 is a perspective view of a cable according to an exemplaryembodiment.

FIG. 10 is a section view of the cable of FIG. 9 taken along line 10-10as shown in FIG. 9.

FIG. 11 is a perspective view of a cable according to another exemplaryembodiment.

FIG. 12 is a section view of the cable of FIG. 11 taken along line 12-12as shown in FIG. 11.

DETAILED DESCRIPTION

FIG. 2 is a cross-sectional view of a fiber optic cable 20 according toa first embodiment of this disclosure. The cable 20 includes a polymerjacket 32 having an outer periphery 34 and a channel periphery 36 thatdefines a channel 38. In the illustrated embodiment, the cross-sectionof the cable 20 is generally circular with an outside diameter 26 ofabout 3.0 millimeters (mm). In this specification, it is understood thatcircular cables may have somewhat irregular cross-sections and varyingdegrees of ovality and/or deviation from an exact circularcross-section. Accordingly, references to “diameters” and “radii” ofcircular cables refer to median or average values, and do not require a“circular” cross-section to have a perfect circular geometry. In thisspecification, the terms “polymer” and “polymeric” indicate materialscomprised primarily of polymers, but allow for the inclusion ofnon-polymer additives and other materials, such as fire-retardantcompounds, etc., and the inclusion of multiple polymers in a blend.

The polymer jacket 32 encloses the channel 38 and the channel 38 mayextend the entire length of the cable 20. The cable 20 further includesa pair of metallic electrical conductors 40, 42 that supply power toperipheral electrical equipment. The electrical conductors 40, 42 can inaddition or alternatively carry data. The electrical conductors 40, 42may include insulating material 44, 46, respectively, about the metallicconducting portions. Alternatively, because the conductors are embeddedin the jacket 32, the insulating layers can be omitted. Data-carryingoptical fibers 48, 50 are arranged in the channel 38. The optical fibers48, 50 may be surrounded by buffer layers. Additional conductors can bewholly or partially embedded within the jacket 32. The conductors 40, 42are stranded conductors which provide tensile strength to the cablewhile retaining good flexibility so that the cable 20 is relatively easyto bend. The electrical conductors 40, 42 also reduce plastic creep inthe cable 20 caused by compressive loads.

The shape of the channel 38 is selected to allow the optical fibers 48,50 to translate within the channel 38 when the cable 20 is bent. Asshown in FIG. 2, the cable 20 cross-section can be bisected by a firstaxis 60 and by a second axis 62, the first and second axes beingperpendicular to one another. The channel 38 has a height or length 70,that is generally measured along the first axis 60, and a width 72, thatis generally measured along the second axis 62. The channel height 70 isgreater than the channel width 72, so that the optical fibers 48, 50have more freedom to move along the first axis 60.

The shape of the channel 38 and the locations of the electricalconductors 40, 42 provide some degree of a preferential bendcharacteristic to the cable 20 to bend either about the first axis 60 orthe second axis 62, as well as allowing the optical fibers 48, 50 totranslate to locations to increase their bend radius and reduce opticalattenuation. Regarding preferential bend, locations of the electricalconductors 40, 42 along the second axis 62 provide an increased materialmoment of inertia along the second axis 62. The cable 20 is thereforeinclined to twist when subjected to bend stresses so that it bends aboutthe second axis 62, which can have the highest material moment ofinertia of any axis through the cable 20. The height 72 of the channel38 provides a path along which the optical fibers 48, 50 can move, asindicated by the double-headed arrow, so as to minimize bend stresses onthe fibers as the cable is bent about the axis 62. When subjected tobending stresses, the cable 20 will tend to bend about the second axis62, and the optical fibers 48, 50 will tend to move in the channel 38 toassume a state of lower strain.

The rectangular cross-section shape of the channel 38 as shown in FIG. 2is idealized in that it is difficult obtain precise geometrical shapeswhile extruding polymers. FIG. 3 is a photograph of a cablecross-section with a generally rectangular channel, but having slightconvexity in the vicinity of the electrical conductors. The use of theterms “height” and “width” in this specification are therefore intendedto allow for variations in the height and width dimensions along thechannel cross-section. For example, the height 70 can be an average ormedian height of the channel 38, based on a plurality of measurementsalong the second axis 62. Likewise, the width 72 can be an average ormedian width of the channel 38 based on a plurality of measurementsalong the first axis 60.

The cross-sectional shape of the channel 38 can be characterized by theaspect ratio of the channel, obtained by dividing the height 70 by thewidth 72. Average or median height and width values can be used toobtain the aspect ratio. According to one aspect of the presentembodiment, the aspect ratio is at least 1.5. In the illustratedembodiment, the aspect ratio is at least 2.0, and falls in the range of2.25-5.0. The electrical conductors 40, 42 are arranged on oppositesides of the channel 38 and can be aligned with the second axis 62. Theelectrical conductors 40, 42 can have geometric centers having a spacing80 along the second axis 62. The spacing 80 can be in the range of0.45-0.8 times the diameter 26 of the cable 20. It is understood thatthe “alignment” of the conductors 40, 42 on the axis 62 does not requirethe geometric centers of the conductors to exactly coincide with thesecond axis 62. To be in alignment, the geometric centers of theconductors may be within, for example, a distance from the second axis62 that is less than 10% of the cable diameter 26. The long dimension ofthe channel 38, or channel height, can be at least 45% of the outsidediameter 26. The optical fibers 48, 50 can be relatively looselydisposed within the channel 38, so that they can translate a significantdistance along the height dimension 70. For example, the fibers 48, 50can be arranged so that they can each translate a distance of at least10% of the cable diameter 26.

EXAMPLE 1

An exemplary cable 20 may have a cross-section as schematically shown inFIG. 2 and as in the photographs shown in FIGS. 3 and 4. The cable 20includes two, 253 micron colored optical fibers. The cable has anaverage diameter 26 in the range of 2.8-3.3 mm, a channel 38 averageheight 70 in the range of 1.4-1.8 mm, an average width 72 in the rangeof 0.45-0.7 mm, and two insulated metallic electrical conductors in therange of 24 to 30 AWG (American wire gauge). The conductors 40, 42 areembedded in the cable jacket 32 during extrusion of the jacket. Theaspect ratio for the channel 38 is in the range of 1.5-4. The electricalconductors 40, 42 are located on opposite sides of the channel 38, andtheir geometric centers are spaced from one another a distance in therange of 1.5-2.0 mm. The cable jacket 32 is comprised primarily ofpolyvinylchloride (PVC).

EXAMPLE 2

An exemplary cable 20 may have a cross-section as generally shown inFIG. 2. The cable 20 includes two colored optical fibers. The cable hasan average diameter 26 in the range of 3.0-3.6 mm, a channel 38 averageheight 70 in the range of 1.4-1.8 mm, an average width 72 in the rangeof 0.45-0.7 mm, and two insulated metallic electrical conductors in therange of 24 to 30 AWG. The conductors 40, 42 are embedded in the cablejacket 32 during extrusion of the jacket. The aspect ratio for thechannel 38 is in the range of 1.5-4. The electrical conductors 40, 42are located on opposite sides of the channel 38, and their geometriccenters are spaced from one another a distance in the range of 1.5-2.0mm. The cable jacket 32 is comprised primarily of PVC.

EXAMPLE 3

An exemplary cable 20 may have a cross-section as generally shown inFIG. 2. The cable 20 includes a single colored optical fiber. The cablehas an average diameter 26 in the range of 2.8-3.6 mm, a channel 38average height 70 in the range of 1.4-1.8 mm, an average width 72 in therange of 0.3-0.6 mm, and two insulated metallic electrical conductors inthe range of 24 to 30 AWG. The conductors 40, 42 are embedded in thecable jacket 32 during extrusion of the jacket. The aspect ratio for thechannel 38 is in the range of 1.5-4. The electrical conductors 40, 42are located on opposite sides of the channel 38, and their geometriccenters are spaced from one another a distance in the range of 1.5-2.0mm. The cable jacket 32 is comprised primarily of PVC.

EXAMPLE 4

An exemplary cable 20 may have a cross-section as generally shown inFIG. 2. The cable 20 includes four colored optical fibers. The cable hasan average diameter 26 in the range of 2.8-3.6 mm, a channel 38 averageheight 70 in the range of 1.4-1.8 mm, an average width 72 in the rangeof 0.5-0.8 mm, and two insulated metallic electrical conductors in therange of 24 to 30 AWG (American wire gauge). The conductors 40, 42 areembedded in the cable jacket 32 during extrusion of the jacket. Theaspect ratio for the channel 38 is in the range of 1.5-4. The electricalconductors 40, 42 are located on opposite sides of the channel 38, andtheir geometric centers are spaced from one another a distance in therange of 1.5-2.0 mm. The cable jacket 32 is comprised primarily of PVC.

In the embodiments shown in FIGS. 2-4, the cables 20 can consistessentially of the conductors 40, 42, insulated or not insulated, thecable jacket 32, buffered or non-buffered optical fibers, and, ifdesired strength elements (not illustrated) such as tensile yarns. Theperiphery 34 of the jacket 32 can constitute the exterior of the cable20 with no additional jacketing or covering layers.

FIG. 5 illustrates a cross-sectional view of a cable 220 according toanother embodiment. FIG. 6 is an exploded perspective view of the cable220. The cable 220 includes a polymer jacket 232 having an outerperiphery 234 and a channel periphery 236 with the channel periphery 236defining a channel 238. In the illustrated embodiment, the cross-sectionof the cable 220 is generally circular with an average diameter 226 ofabout 3.0 millimeters (mm). The polymer jacket 232 encloses the channel238 and the channel 238 may extend the entire length of the cable 220.The cable 220 further includes a pair of insulated metallic electricalconductors 240, 242. Data-carrying optical fibers 248, 250 are alsoincluded within the channel 238. The shape of the channel 238 isselected to allow the optical fibers 248, 250 to translate when thecable 220 is bent. As shown in FIG. 5, the cable 220 cross-section canbe bisected by a first axis 260 and by a second axis 262, the first andsecond axes being perpendicular to one another. The channel 238 has aheight or length 270, and a width 272, where the height 270 is greaterthan the channel width 272 so that the optical fibers 248, 250 have morefreedom to move along the first axis 260.

The cable 220 also includes one or more tensile strength members in thechannel 238. The tensile strength members are shown in FIGS. 5 and 6 astwo discrete elements, numbered 280 and 282. The tensile strengthmembers can, however, comprise loosely packed tensile yarns that areessentially distributed in the channel 238 in a nonuniform manner. Thetensile strength members can be formed from tensile yarns, includingaramid yarns. The strength members can provide tensile strength to thecable, as well as providing coupling of the optical fibers 248, 250 tothe jacket 232. FIG. 7 is a photograph of a cross-section of a cablecorresponding generally to the cross-section in FIG. 5. The tensileyarns shown in the photograph are nonuniformly distributed in thechannel. The strength material 280, 282 is loosely packed enough suchthat it allows the optical fibers to move within the channel 238.

In the illustrated embodiment, the values and ranges discussed withreference to the cable cross-section shown in FIG. 2 for cable diameter,channel width, channel height, conductor spacing, and aspect ratio areall applicable to the cable shown in FIGS. 5-7.

EXAMPLE 5

An exemplary cable having a cross-section as shown in FIG. 5 has anaverage diameter in the range of 2.8-3.3 mm, a channel having an averageheight in the range of 1.4-1.8 mm, an average width in the range of0.45-0.7 mm, and two insulated electrical conductors in the range of 24to 30 AWG. The conductors are embedded in the cable jacket duringextrusion of the jacket. The aspect ratio for the channel is in therange of 2.5-3.5. The electrical conductors are located on oppositesides of the channel, and their centerlines are spaced from one anothera distance in the range of 1.6-1.9 mm. The cable jacket is comprised ofcopolymer thermoplastic elastomer (TPE). The cable 20 includes twocolored optical fibers. KEVLAR™ aramid yarns are provided in thechannel.

FIG. 8 is a cross-sectional view of a fiber optic cable 320 according toanother embodiment of this disclosure. The cable 320 includes a polymerjacket 330 having an outer section 332 formed from a first polymericmaterial, with a periphery 334, and an inner section 340, formed from asecond polymeric material, disposed within the outer portion 332. Theinner section 340 can be formed from a polymer that is coextruded withthe outer portion 332. The interior of the jacket 332 is accordingly indirect contact with an outer periphery 342 of the inner section 340,completely enclosing the inner section. According to one aspect of thepresent embodiment, the inner section 340 can have a modulus ofelasticity that is greater than the outer section 332.

A channel periphery 336 defines a channel 338 in the inner section 340.In the illustrated embodiment, the cross-section of the cable 320 isgenerally circular with a diameter of about 3.0 mm. The channel 338 mayextend the entire length of the cable 320. The cable 320 furtherincludes a pair of insulated metallic electrical conductors 344, 346that supply power to peripheral electrical equipment. The electricalconductors 344, 346 can in addition or alternatively carry data. Theelectrical conductors 344, 346 can be embedded in the jacket 332 so thatinsulating material can be omitted. Data-carrying optical fibers 352,354 are also included within the channel 338. The optical fibers 352,354 may be surrounded by colored buffer layers.

As shown in FIG. 8, the cable 320 cross-section can be bisected by afirst axis 360 and by a second axis 362, the first and second axes beingperpendicular to one another. The inner section 340 has a width, ormajor dimension 364, that is measured along the second axis 362. A minordimension 366 or height of the inner section 340 is measured along thefirst axis 360. The inner section 340 has a curved outer periphery 342and the minor dimension 366 is smaller than the major dimension 364, sothat it resembles an ellipse. The shape of the channel 338 is selectedto allow the optical fibers 352, 354 to translate within the channel 338when the cable 320 is bent. The channel 338 has a height or length 370,that is generally measured along the first axis 360, and a width 372,that is generally measured along the second axis 362. The channel height370 is greater than the channel width 372, so that the optical fibers352, 354 have more freedom to move along the first axis 360. The shapeof the channel 338 and the locations of the electrical conductors 344,346 provide preferential bend characteristics to the cable 320 to bendeither about the first axis 360 or the second axis 362, as well asallowing the optical fibers 352, 354 to translate to locations toincrease their bend radius and reduce optical attenuation. By formingthe jacket 330 from a relatively low modulus outer section 332 and arelatively high modulus inner section 340, the stability of the channel338 is improved.

According to one aspect, the low modulus outer section 332 reducestorsional forces in bending. The high modulus inner section 340 addsstrength to the side walls of the channel 338 and resists torsionalforces. Use of low modulus material in the outer section 332 also helpsimprove the flexibility in handling of the cable 320 as compared to acable having a uniform high modulus jacket. The inner core may also beindependent of the outer jacket.

Examples of high modulus materials suitable for use in the inner section340 are high modulus polyvinylchloride (PVC), thermoplastic elastomer(TPE), nylon, and polyethylene. Examples of low modulus materialssuitable for use in the outer section 332 are low modulus PVC, TPE, andthermoplastic urethane (TPU). The inner section 340 can have a modulusof elasticity that is at least 100% higher than that of the outersection 332. The polymer of the inner section 340 has a cross-sectionalarea that is at least 20% of the total cross-sectional area of the cable320 cross-section.

The values and ranges discussed with reference to the cablecross-section shown in FIG. 2 for cable diameter, channel width, channelheight, conductor spacing, and aspect ratio are all applicable to thecable shown in FIG. 8.

EXAMPLE 6

A cable 320 as shown in FIG. 8 has a diameter in the range of 2.8-3.2 mmand two electrical conductors in the range of 24-28 AWG. The cablejacket 330 has an inner section 340 with a modulus of elasticity that isat least twice as large as the modulus of elasticity of the outersection 332.

Referring to FIGS. 9-12, cables 410, 510 may include more than twodata-carrying optical fibers 412, 512 such as four optical fibers percable 410, 510, with or without tensile yarn 514 (FIGS. 11-12). Othernumbers of optical fibers 412, 512 may be used as well, such as onemulti-mode optical fiber, twelve single-mode optical fibers, ordifferent numbers and types of optical fibers including a glass core andcladding.

In some embodiments, the conductors 416, 418, 516, 518 (e.g., strengthmembers, reinforcement structures, bend-control elements) are conductive(i.e., made from electrically conductive material) but are not intendedto or do not actively conduct electricity or supply power to peripheralelectrical equipment during operation of associated hardware. Suchconductors 416, 418, 516, 518 may still serve to provide strength to thecable 410, 510 and/or to provide a bend preference to the cable 410, 510so that the optical fibers 412, 512 generally move in the longerdimension of the channel 420, 520 when the cable 410, 510 is bent orwound. In some such embodiments, the conductors 416, 418, 516, 518 maybe decoupled or isolated electrically in connector(s) attached on end(s)of the cable 410, 510 and/or elsewhere, so as to prevent or block activeelectrical conduction via the conductors 416, 418, 516, 518 between theassociated hardware. In other embodiments, one of the conductors 416,418, 516, 518 may actively conduct electricity or electricalcommunications, while the other is conductive but decoupled electricallyfrom associated hardware. In such an arrangement, the conductors 416,418, 516, 518 offset one another structurally and geometrically,providing bend preference and strength to the cable 410, 510, but onlyone of the conductors 416, 418, 516, 518 actively communicateselectrically during operation of the associate hardware.

In contemplated embodiments, different numbers of conductors 416, 418,516, 518 may be used, such as three or four conductors arranged alongthe same axis, to control bending and to provide strength and/orconduits for electrical communication. In some embodiments, theconductors are metallic, such as comprising or consisting of copper,steel, stainless steel (e.g., stranded stainless steel wire,seven-strand stainless steel wire), aluminum, or other metals or alloysof such metals. For example, in some embodiments, copper may be used forconductors 416, 418, 516, 518 intended for data communication, whilestainless steel may be used for conductors 416, 418, 516, 518 intendedprimarily for or only for strength and bend control. The stranding layorientation (e.g., helical direction) of stranded conductors 416, 418,516, 518 may be opposite to one another to offset one another andfacilitate straight formation of the associated cable 410, 510.

In some embodiments, the diameter of the cable 410, 510 using steelconductors 416, 418, 516, 518 may be less than the diameter of a similarcable 410, 510 using copper conductors 416, 418, 516, 518 at least inpart because of the associated strength differences of the materials.For example, a steel conductor 416, 418 may be in the range of 0.30 mmin diameter or less, while a copper conductor 516, 518 may be in thearrange of 0.38 mm. As such, the diameter of cable 410 using steelconductors 416, 418 with four optical fibers 412, 512 may be in therange of 2.9 to 3.5 mm. The channel 420, 520 may be in the range of 0.4to 0.5 mm in width and 1.0 to 1.75 mm in height. According to anexemplary embodiment, the channel 420, 520 is oriented with the narrowerdirection (e.g., width) aligned with the axis extending between thecenters of the conductors 416, 418, 516, 518 (where the conductors 416,418, 516, 518 may not be intended to actively conduct electricity duringoperation of associated hardware). The interior of the channel 420, 520may be spaced apart from the conductors 416, 418, 516, 518 by a distanceD₁, D₂ of at least 0.15 mm, such as about 0.2 mm, providing sufficientseparation to prevent pinching or other direct- or indirect-interactionthat would attenuate, damage, and/or otherwise influence the opticalfibers 412, 512, between the conductors 416, 418, 516, 518 when thecable 410, 510 is bent.

In other contemplated embodiments, non-conductive materials—such asceramic, plastic, glass-reinforced plastic, or other non-conductivematerials—may be used to provide strength and bend control in place ofthe conductors 416, 418, 516, 518. Such non-conductive members may beshaped and positioned similarly to the conductors 416, 418, 516, 518,but dimensions of the non-conductive members may be greater due todifferences in the respective material properties. For example, steelconductors 416, 418 may be preferred over glass-reinforced strengthelements because the steel conductors 416, 418, may allow for a smallercable 410 cross-section (i.e., area of a face transverse to the lengthof the cable 410), or a cross-section appropriate for a particular useof the cable 410.

Throughout the foregoing disclosure, the adjective “about” has been usedin numerous locations preceding an amount. Other embodiments of thisdisclosure are like the above-discussed embodiments, except that theadjective “about” is optional and may be omitted. It will be understoodto the skilled artisan that the methods disclosed herein to controloptical fiber position within a fiber optic cable are not mutuallyexclusive and may be used in any combination as required to achieveappropriate control of optical fiber position.

The construction and arrangements of the cable, as shown in the variousexemplary embodiments, are illustrative only. Although only a fewembodiments have been described in detail in this disclosure, manymodifications are possible (e.g., variations in sizes, dimensions,structures, shapes, and proportions of the various elements, values ofparameters, mounting arrangements, use of materials, colors,orientations, etc.) without materially departing from the novelteachings and advantages of the subject matter described herein. Forexample, as will be understood by those of ordinary skill in the art,features and attributes associated with embodiments shown in one of theFigures may be applied to embodiments shown in others of the Figures.Also, some elements shown as integrally formed may be constructed ofmultiple parts or elements, the position of elements may be reversed orotherwise varied, and the nature or number of discrete elements orpositions may be altered or varied. The order or sequence of anyprocess, logical algorithm, or method steps may be varied orre-sequenced according to alternative embodiments. Other substitutions,modifications, changes and omissions may also be made in the design,operating conditions and arrangement of the various exemplaryembodiments without departing from the scope of the present invention.

What is claimed is:
 1. A fiber optic cable configured for use inconsumer electronics applications, including connecting computerperipherals, the fiber optic cable comprising: (A) colored opticalfibers, each of the optical fibers comprising a glass core and cladding,wherein the optical fibers are non-buffered optical fibers; (B) apolymer jacket having an outer periphery and a channel periphery thatdefines a channel through which the optical fibers extend, wherein thechannel extends the entire length of the cable, wherein the shape of thechannel is selected to allow the optical fibers to translate thereinwhen the cable is bent; wherein the channel has a height that isgenerally measured along a first axis and a width that is generallymeasured along a second axis, wherein the height of the channel isgreater than the width of the channel, wherein the optical fibers maymove along the first axis; wherein the channel has an aspect ratio,obtained by dividing the height of the channel by the width of thechannel, of at least 1.5; wherein the outer periphery of the jacketconstitutes the exterior of the fiber optic cable; wherein the fiberoptic cable is circular in cross-section; wherein the fiber optic cablehas a particularly small footprint such that the diameter of thecircular cross-section is about 3 millimeters; (C) first and secondbend-control elements, wherein the bend-control elements provide apreferential bend characteristic to the fiber optic cable such that thefiber optic cable is inclined to twist when subjected to bendingstresses so that the fiber optic cable bends about the second axis andthe optical fibers will tend to move in the channel to assume a state oflower strain; wherein the bend control elements are arranged on oppositesides of the channel from one another and are aligned with the secondaxis, wherein the bend-control elements are wholly embedded in thejacket, wherein the bend control elements compriseelectrically-conductive material and wherein the electrically-conductivematerial is metallic; wherein the bend control elements are spaced apartfrom the interior of the channel by a distance of at least 0.15millimeters, thereby providing sufficient separation to mitigatepinching or other direct- or indirect-interaction that may attenuate,damage, or otherwise influence the optical fibers when the cable isbent.
 2. The fiber optic cable of claim 1, wherein theelectrically-conductive material is steel, and wherein the bend controlelements are non-insulated in that the steel is embedded in the jacketwithout additional insulating material.
 3. The fiber optic cable ofclaim 2, wherein the steel of the bend control elements is stranded,thereby providing tensile strength to the cable while retaining goodflexibility so that the fiber optic cable is relatively easy to bend. 4.The fiber optic cable of claim 3, wherein the bend-control elements havea diameter that is in the range of about 0.3 millimeters or less,facilitating the particularly small footprint of the fiber optic cable.5. The fiber optic cable of claim 1, wherein the fiber optic cable notmerely comprises, but consists essentially of elements (A), (B), and(C).
 6. The fiber optic cable of claim 5, wherein the diameter of thefiber optic cable is, more specifically, in the range of 2.9 to 3.5millimeters.
 7. The fiber optic cable of claim 6, wherein the opticalfibers are precisely four optical fibers.
 8. A fiber optic cableconfigured for use in consumer electronics applications, includingconnecting computer peripherals, the fiber optic cable comprising: (A)colored optical fibers, each of the optical fibers comprising a glasscore and cladding, wherein the optical fibers are non-buffered opticalfibers; (B) a polymer jacket having an outer periphery and a channelperiphery that defines a channel through which the optical fibersextend, wherein the shape of the channel is selected to allow theoptical fibers to translate therein when the cable is bent; wherein thecable cross-section can be bisected by a first axis and by a secondaxis, the first and second axes being perpendicular to one another,wherein the channel has a height that is generally measured along thefirst axis and a width that is generally measured along the second axis,wherein the height of the channel is greater than the width of thechannel, wherein the optical fibers may move along the first axis;wherein the channel has an aspect ratio, obtained by dividing the heightof the channel by the width of the channel, of at least 1.5; wherein theouter periphery of the jacket constitutes the exterior of the fiberoptic cable; wherein the fiber optic cable is circular in cross-section;wherein the fiber optic cable has a particularly small footprint suchthat the diameter of the circular cross-section is about 3 millimeters;(C) first and second bend-control elements, wherein the bend-controlelements provide a preferential bend characteristic to the fiber opticcable such that the fiber optic cable is inclined to twist whensubjected to bending stresses so that the fiber optic cable bends aboutthe second axis and the optical fibers will tend to move in the channelto assume a state of lower strain; wherein the bend control elements arearranged on opposite sides of the channel from one another and arealigned with the second axis, wherein the bend-control elements arewholly embedded in the jacket, wherein the bend control elementscomprise electrically-conductive material and wherein theelectrically-conductive material is metallic; wherein the bend controlelements are spaced apart from the interior of the channel by a distanceof at least 0.15 millimeters, thereby providing sufficient separation tomitigate pinching or other direct- or indirect-interaction that mayattenuate, damage, or otherwise influence the optical fibers when thecable is bent.
 9. The fiber optic cable of claim 8, wherein theelectrically-conductive material is steel, wherein the bend controlelements are non-insulated in that the steel is embedded in the jacketwithout additional insulating material, and wherein the steel of thebend control elements is stranded, thereby providing tensile strength tothe cable while retaining good flexibility so that the fiber optic cableis relatively easy to bend.
 10. The fiber optic cable of claim 9,wherein the bend-control elements have a diameter that is in the rangeof about 0.3 millimeters or less, facilitating the particularly smallfootprint of the fiber optic cable.
 11. The fiber optic cable of claim8, wherein the fiber optic cable not merely comprises, but consistsessentially of elements (A), (B), and (C).
 12. The fiber optic cable ofclaim 11, wherein the diameter of the fiber optic cable is, morespecifically, in the range of 2.9 to 3.5 millimeters.
 13. The fiberoptic cable of claim 12, wherein the optical fibers are precisely fouroptical fibers.
 14. A fiber optic cable configured for use in consumerelectronics applications, the fiber optic cable comprising: (A) coloredoptical fibers, each of the optical fibers comprising a glass core andcladding, wherein the optical fibers are non-buffered optical fibers;(B) a polymer jacket having an outer periphery and a channel peripherythat defines a channel through which the optical fibers extend, whereinthe channel extends the entire length of the cable, wherein the shape ofthe channel is selected to allow the optical fibers to translate thereinwhen the cable is bent; wherein the cable cross-section can be bisectedby a first axis and by a second axis, the first and second axes beingperpendicular to one another, wherein the channel has a height that isgenerally measured along the first axis and a width that is generallymeasured along the second axis, wherein the height of the channel isgreater than the width of the channel, wherein the optical fibers maymove along the first axis; wherein the channel has an aspect ratio,obtained by dividing the height of the channel by the width of thechannel, of at least 1.5; wherein the outer periphery of the jacketconstitutes the exterior of the fiber optic cable; wherein the fiberoptic cable is circular in cross-section; wherein the fiber optic cablehas a particularly small footprint such that the diameter of thecircular cross-section is about 3 millimeters; (C) first and secondbend-control elements, wherein the bend-control elements provide apreferential bend characteristic to the fiber optic cable such that thefiber optic cable is inclined to twist when subjected to bendingstresses so that the fiber optic cable bends about the second axis andthe optical fibers will tend to move in the channel; wherein the bendcontrol elements are arranged on opposite sides of the channel from oneanother and are aligned with the second axis, wherein the bend-controlelements are wholly embedded in the jacket, wherein the bend controlelements comprise electrically-conductive material and wherein theelectrically-conductive material is metallic; wherein the bend controlelements are spaced apart from the interior of the channel by a distanceof at least 0.15 millimeters.
 15. The fiber optic cable of claim 14,wherein the electrically-conductive material is steel, and wherein thebend control elements are non-insulated in that the steel is embedded inthe jacket without additional insulating material.
 16. The fiber opticcable of claim 15, wherein the steel of the bend control elements isstranded, thereby providing tensile strength to the cable whileretaining good flexibility so that the fiber optic cable is relativelyeasy to bend.
 17. The fiber optic cable of claim 16, wherein thebend-control elements have a diameter that is in the range of about 0.3millimeters or less, facilitating the particularly small footprint ofthe fiber optic cable.
 18. The fiber optic cable of claim 14, whereinthe fiber optic cable not merely comprises, but consists essentially ofelements (A), (B), and (C).
 19. The fiber optic cable of claim 18,wherein the diameter of the fiber optic cable is, more specifically, inthe range of 2.9 to 3.5 millimeters.
 20. The fiber optic cable of claim19, wherein the optical fibers are precisely four optical fibers.